Despite the availability of effective antibiotics for treatment of acute otitis media (AOM), treatment failures, persistent effusions and recurrences are common. One factor associated with poor treatment outcome is concurrent viral infection, which we have shown to be associated with increased levels of inflammatory mediators in the middle ear (ME) fluids. We propose that inflammatory mediators, particularly histamine and leukotrienes, play a significant role in both the pathogenesis of and recovery from AOM, and therefore will test whether adjuvant therapy aimed at counteracting histamine actions (antihistamine), and/or inhibiting formation of leukotrienes and other inflammatory substances (corticosteroid), in addition to antibiotic, will improve acute and long- term outcome of AOM by reducing the degree of the initial inflammation. The efficacy of the adjuvant drugs will be tested in 2 separate, simultaneous studies which use a randomized, double-blind, placebo- controlled design over a 4-year period. In Study 1, 120 patients will be enrolled at the onset of AOM. Tympanocentesis will be performed prior to and 5 days into therapy to measure histamine and leukotriene levels and document bacterial and viral etiology. These patients will be followed for the duration of ME effusion. They will be followed by home visits with tympanometry and telephone contacts until their next acute episode, and then assigned to treatment groups.